Peripheral blood lymphocyte subset count in COVID-19 patients

Background: (COVID-19) pathophysiology and the predictive factors are not fully understood, but lymphocyte dysregulation appears to play a role. Aim and Objectives: To explore the clinical value of lymphocyte subset changes in COVID-19 patients' peripheral blood, which may illustrate the pathogenesis of COVID-19. Methods: This is prospective cohort study of 73 hospitalized patients with confirmed COVID-19 who were classified into two groups: non-severe and severe. Lymphocyte subsets (CD3, CD4, CD8, CD19, and CD56) were assessed using flow cytometry. Results Lymphocyte gate, CD3, CD4, CD8, and CD56 counts were significantly reduced in severe cases compared with nonsevere cases (P0.001, 0.006, 0.016, 0.011, and 0.008 respectively). Patients were divided into two groups according to cut off age (<50 and >= 50years) and (NLR) (NLR <4.14 and NLR >= 4.14). There was a significant difference in severe illness probability in two groups P0.001 and 0.001 respectively). Then, patients were divided into four groups by both NLR cutoff and age, There also significant difference in severe illness probability between four groups (P<0.001). Conclusion Based on our data, management of patients with COVID-19 pneumonia can be improved based on NLR and age model. We suggest that patients with NLR >= 4.14 should be admitted to isolation ward with close follow-up and actively transfer to intensive care unit. (c) 2023 The Egyptian Journal of Haematology